Conventional toilets typically employ a generally rectangular porcelain tank mounted immediately above a porcelain bowl from which a quantity of water is rapidly drained in order to flush waste from the bowl into the sewer system. Common designs use a flapper valve made of an elastomeric material that covers the drain outlet of the tank. When the flush handle on the outside of the tank is manually depressed, the flapper valve is lifted and the head of water in the tank drains through the drain outlet into the bowl, thereby flushing the contents of the bowl into the sewer system. The flapper valve is typically designed with an inverted air chamber so that it initially floats as it is lifted away from the drain outlet in the bottom of the tank. This allows sufficient flushing water to flow into the bowl even if the user immediately releases the flush handle. When the water level in the tank drops, the tank is automatically refilled through a fill valve connected to a high pressure water supply line.
The typical fill valve comprises a ballcock or pilot fill valve mounted in the tank on top of a riser assembly which extends through an opening in the bottom of the tank and is connected to a pressurized water line. When the tank drains, a float connected to the ballcock or pilot fill valve descends. This activates the ballcock or pilot fill valve and it allows the tank to refill with water at a rate much slower than the rate at which water flows through the drain outlet. When the tank is nearly empty, the flapper valve closes. At the same time water from the ballcock or pilot fill valve enters an overflow tube and refills the bowl to the normal standing water level to provide a trap seal. Once the float reaches a predetermined height indicating that the tank is full, the ballcock or pilot fill valve completely shuts off the water flow into the tank.
The foregoing general conventional arrangement is widely used today. One pilot fill valve construction that was devised and has achieved wide market acceptance and success is disclosed in U.S. Pat. No. 6,003,541 titled “Unitary Float and Arm for Float Operated Valve.” Other fill valves of related construction include U.S. Pat. No. 5,975,125 titled “Combined Filter and Noise Suppressor for Fill Valve;” U.S. Pat. No. 5,836,346 titled “Pilot Operated Diaphragm Fill Valve;” U.S. Pat. No. 5,715,859 titled “Adjustable Fill Vale Assembly;” and, more recently, U.S. Pat. Nos. 8,387,652 and 9,062,795 both titled “Water Saver Fill Valve and Assembly” both being disclosures of this inventor. The disclosures relative to each of the foregoing constructs are incorporated herein by reference.
Fill valves made in accordance with the foregoing construction include a riser assembly, a valve housing mounted on an upper end of the riser assembly, and a pilot operated diaphragm valve mounted in the valve housing. A float housing is connected to the valve housing. A float arm of a combination float and float arm has a first end pivotally connected to the valve housing for opening and closing a pilot orifice in the diaphragm valve. A second end of the float arm is connected to the float. The float is located in the float housing which has an inlet opening for allowing water to spill into the float housing so that the float rises upwardly and the first end of the float arm fully seals off the pilot orifice.